(1) Field of the Invention
The present invention relates to a waterproof packing which adheres to an outer peripheral surface of an electric wire and an inner peripheral surface of a packing-mounting side with a thermoplastic adhesive so as to achieve secure waterproofing, a waterproof connector using such a waterproof packing, and a process for producing such a waterproof connector.
(2) Description of the Related Art
FIG. 16 shows an example of a conventional waterproof connector and a process for producing the conventional waterproof connector (see Japanese Patent Application Laid-Open No. H10-321287).
The waterproof connector 81 includes a connector housing 82 made of synthetic resin, cover 83 made of synthetic resin for covering the connector housing 82, and a cylindrical waterproof packing 85 being mounted on, an outer peripheral surface of an insulating coating of an electric wire 84. The waterproof packing 85 is made of material such as polyester or elastomer.
A rear half of the connector housing 82 is opened, a plate-shaped extending part 86 of a terminal is arranged in an opening of the connector housing 82, the electric wire 84 coated with an insulation is arranged on the terminal extending part 86, the waterproof packing 85 is received in the opening, the waterproof packing 85 is covered with the cover 83 from above, the electric wire 84 and the waterproof packing 85 are pressed by a projection of the cover 83, and on such a condition the cover 83 is ultrasonically vibrated relatively to the connector housing 82.
Both ends 88 of the cover 83 are welded to and integrated with a substrate 87 of the connector housing 82, the insulating coating of the electric wire 84 is melted so that a conductor part of the electric wire 84 is exposed and connected to the terminal extending part 86, and the waterproof packing 85 is melted so as to close the opening of the connector housing 82, thereby preventing water from entering from the outside.
However, as for the conventional waterproof connector and the process for producing the conventional waterproof connector as described above, there is a problem that mechanization of an operation is difficult and many man-hour is required due to troublesome machining since the electric wire 84 must be passed through the cylindrical waterproof packing 85 one by one and a tape-shaped waterproof member must be wound around the waterproof packing 85. Further, when such a member is used that the whole of the waterproof packing is melted, a long time period is required for heating, and when an outer diameter of the waterproof packing 85 is small, there is a problem that upon melting, a gap tends to occur between an outer peripheral surface of the electric wire 84 and an inner peripheral surface of the waterproof packing 85 and between an outer peripheral surface of the waterproof packing 85 and an inner surface of the connector housing 82 that is the side of mounting, resulting in that there are many control-requiring points such as a setting amount of a waterproof member and a position for mounting of the waterproof member, causing unstability of quality. Furthermore, when the cover 83 is melted to adhere to the connector housing 82, the electric wire 84 is melted to adhere to the terminal extending part 86, and simultaneously the waterproof packing 85 is melted to adhere to the connector housing 82, there is a problem that it is difficult to judge whether the waterproof packing 85 is melted or not. Further, since the cover 83 is permanently fixed to the connector housing 82, there is a problem that it is difficult to disassemble the waterproof connector 81 efficiently so as to extract the terminal 86 made of metal for the purpose of maintenance or recycling.